You've fallen and hit your head. It hurts a little, but you're not bleeding and you feel okay. Do you have a head injury, or are you fine? Knowing how to tell a minor head injury from a serious one could literally save your life. Let's talk about head injuries.

Millions of people get head injuries every year. They get into car accidents or fights, they fall, or they get hit in the head while playing sports or working on the job. Most head injuries are minor, because your head comes equipped with its own natural hard hat, a protective skull that surrounds and protects your brain. But sometimes that protection isn't enough. More than a half-million people each year get head injuries severe enough to send them to the hospital.

The most common type of head injury is a concussion. That's when a hit in the head makes your brain jiggle around in your skull. You can also get a bruise on your brain, called a contusion. Brain contusions are a lot more serious than bruises from a bump on the arm or leg. Other types of head injuries include a fractured skull or a cut on your scalp.

If you get hit in the head or fall and you don't bleed, you've got a closed head injury. If an object enters your brain, like glass from a windshield during a car accident or a bullet from a gunshot, then you have an open head injury.

It can be very hard to tell if you've got a minor closed head injury or a serious one. Your head might look perfectly fine from the outside, when you actually have bleeding or swelling inside your brain.

To tell the difference, look for other signs of a serious head injury, such as a severe headache; Clear or bloody fluid coming from your nose, ears, or mouth; Confusion, drowsiness, or a loss of consciousness; Changes in the way you hear, see, taste, or smell; memory loss; mood changes or strange behaviors; slurred speech or recurrent vomiting.

If you or someone else has any of these symptoms, call for medical help right away.

If you don't have these symptoms and you think it's just a minor head injury, you probably don't need to be treated. Just ask a friend or family member to keep an eye on you. If it's your child or someone else with the head injury, wake them up from sleep every 2 or 3 hours to ask questions like, "Where are you?" and "What's your name?" just to make sure they're alert.

If you're in any doubt about whether a head injury is serious, play it safe and get medical help. To play it even safer, protect your head during any activities that could lead to an injury. Wear a helmet whenever you skateboard, roller skate, ski, snowboard, or ride a bike or motorcycle. Put on your seatbelt whenever you're in the car. And put kids in an age-appropriate car seat or booster seat.